1. Field of the Invention
This invention relates to a group III nitride semiconductor light emitting element and, in particular, to a group III nitride semiconductor light emitting element that uses as a light emitting layer an MQW (multiquantum well) structure with a well layer such as InGaN layer.
2. Description of the Related Art
In recent years, light emitting apparatuses using a semiconductor element (light emitting element) such as an LED (light emitting diode) and a LD (laser diode) are widely used as a light source since they are smaller, more excellent in power efficiency or longer in lifetime than light bulbs.
In such a semiconductor light emitting element, a blue/green light emitting diode and a violet semiconductor laser diode using an active layer (light emitting layer) with an InxGa1−xN MQW structure have been commercialized already.
A conventional group III nitride semiconductor light emitting element is known that plural well layers composing the light emitting layer are set to be different from each other in composition ratio of components to compose the well layers (e.g., JP-A-10-022525).
However, the conventional group III nitride semiconductor light emitting element has a problem that the well layers each have an emission wavelength different from each other to cause deterioration in color purity and reduction in emission intensity, since the screening effect is different between the well layers due to a difference in piezooptical effect level and in carrier concentration therebetween.